What is the dose and frequency of Macrobid (Nitrofurantoin) for Urinary Tract Infection (UTI)?

From the Guidelines

The recommended dose and frequency of Macrobid (Nitrofurantoin) for Urinary Tract Infection (UTI) is 100 mg twice daily for 5 days.

Key Points

• The dosage is based on the guidelines outlined by the Infectious Diseases Society of America (IDSA) and the European Society for Microbiology and Infectious Diseases (ESCMID) 1.
• Nitrofurantoin monohydrate/macrocrystals is an appropriate choice for therapy due to minimal resistance and propensity for collateral damage, with efficacy comparable to trimethoprim-sulfamethoxazole (TMP-SMX) 1.
• The studies demonstrate a clinical cure rate with nitrofurantoin of 88% - 93% and a bacterial cure rate of 81% - 92% 1.
• The recommended treatment duration for uncomplicated cystitis is 5 days for nitrofurantoin, which is equivalent in clinical and microbiological cure rates to a 3-day course of TMP-SMX 1.
• It is essential to note that the choice of antibiotic should be based on local resistance rates and the susceptibility of the infecting strain 1.
• The use of nitrofurantoin is supported by multiple studies, including a meta-analysis that demonstrates its efficacy in treating acute uncomplicated cystitis 1.

From the Research

Dose and Frequency of Macrobid (Nitrofurantoin) for UTI

• The recommended dose and frequency of Macrobid (Nitrofurantoin) for Urinary Tract Infection (UTI) is not consistently stated across studies 2, 3, 4, 5, 6.
• A study from 2010 found that nitrofurantoin sustained release 100 mg twice daily for 7 days was effective in treating acute lower urinary tract infections in adults, with a microbial eradication rate of 92.3% 6.
• Another study from 2015 found that nitrofurantoin given for 5 or 7 days had good clinical and microbiological efficacy for UTI, with clinical cure rates varying between 79% and 92% 4.
• A 2023 review of international guidelines found that the evidence base for nitrofurantoin has been interpreted in different ways, and that UK guidelines recommending 3 days of nitrofurantoin at 100 mg twice daily may not be supported by direct evidence 5.
• The optimal dose and frequency of Macrobid (Nitrofurantoin) for UTI may vary depending on the specific patient population and the severity of the infection, and further research is needed to determine the most effective treatment regimen 2, 3, 4, 5, 6.

Specific Dosing Regimens

• 100 mg twice daily for 7 days 6
• 5-7 days of nitrofurantoin 4
• 3 days of nitrofurantoin at 100 mg twice daily (recommended in UK guidelines, but may not be supported by direct evidence) 5

Efficacy and Safety

• Nitrofurantoin has been shown to be effective in treating UTI, with good clinical and microbiological efficacy 4, 6.
• The development of resistance to nitrofurantoin is low 6.
• Nitrofurantoin is generally well tolerated, with mild and reversible adverse events, predominantly gastrointestinal 4, 6.